Disposable cups and mugs are very popular but they do have the disadvantage that they are light and therefore easily knocked over. Moreover, disposable cups may be difficult to hold when the content is hot. Even further disposable cups do not have handle and they may not insulate the contents well.
Many coffee shop customers bring their own cups to be filled at retail outlets. Even if this is environmentally beneficial, it creates the problem of a dirty coffee cup. After having the beverage from their own cup, the customer needs either to wash the cup or to transport a dirty cup back to their home or office. The present invention provides a novel solution to this problem.
U.S. Pat. No. 5,816,501 describes a disposable paint container liner, where a lid is removed from a paint cup and a disposable liner bag is inserted into the cup while an open end of the liner bag extends from the open cup end. The open liner bag end is folded over and protects the cup end and paint is poured into the liner bag. A disposable lid is placed over the open cup end and the open liner bag end is folded inwardly over the disposable lid. The paint cup lid is then attached to the paint cup, clamping the liner bag and disposable lid in place.
U.S. Patent application publication 20100243656 describes a liner insert for a supply bucket of a liquid siphoning system, such as a siphon for an airless paint sprayer. The liner is adapted to simply slide into a bucket that corresponds to its size. The liners preferably are disposable, and may be manufactured, such as from plastic, in various sizes and shapes to accommodate different supply bucket and siphon geometries.
U.S. Pat. No. 3,580,468 describes a double-walled, disposable container that is formed by combining a conventional outer paper cup and an inner liner cup formed of thin-walled thermoformed seamless plastic. The inner liner has a rim or lip at the top which is curled over, around and under the rim of the outer paper cup so as to snugly embrace the same. U.S. Pat. No. 4,134,492 describes a container for a beverage concentrate, where a cup and a plastic film liner positioning the beverage concentrate between the liner and the cup bottom is provided. The liner overlaps the rim of the cup and is attached thereto so as to form a convenient easily handled section enabling the liner to be removed when the beverage concentrate is to be used as by adding water thereto.
U.S. patent application publication 20040055989 that describes a sipping cup for toddlers including a reusable cup portion and securing ring and a disposable top portion and liquid holding bag. The liquid holding bag is inserted into the reusable cup portion, a desired liquid placed in the bag, a disposable top portion is placed over the liquid filled bag, and a reusable top portion is then placed on top and screwed down onto the reusable cup portion. After use, the disposable top portion and liquid holding bag may be discarded while retaining the reusable cup portion and securing ring for future reuse.
U.S. Pat. No. 5,685,480 discloses a disposable insulated drinking cup that includes an inner liner, an outer annular shell, and an air-filled spacer between the liner and shell. The spacer includes a corrugated wall adhered to a backing sheet. Both the corrugated wall and backing sheet are of thin-wall construction to maximize the air volume and insulation properties of the spacer.
U.S. Pat. No. 6,758,363 discloses a portable beverage container that has a body and a liner fitting inside the body. The body has a handle for easy grasping. The material of the body and the liner is dishwasher safe, preferably aluminum, steel or thermoplastic.
U.S. Reissued Pat. No. RE42,421 that describes an insulated cup holder including a double walled insulating vessel including an inner liner and an outer liner spaced defining an insulating space and snugly receives a conventional cup so as to insulate the contents of the cup to assist in maintaining its temperature at a desired level.
Chinese patent application publication CN1996096243569U describes a cup with an internal plastic liner. In this invention the liner and the cup is a unit in the sense that the liner when inserted into the cup is plugged and fixed to notches in the cup body. Therefore, the liner is unsuitable to be used with any other cup.
Accordingly, even if there is a number of various kinds of liners disclosed in the prior art and some of them meant to be used with coffee cups and mugs, there is a remaining need for a disposable mug liner that would be easy to use, and would fit inside any coffee mug.